# 课本P109
word = input("provide a word to search for vowels:")
found = {} #创建空字典
#初始化频度
found['a'] = 0
found['e'] = 0
found['i'] = 0
found['o'] = 0
found['u'] = 0
for  letter in word:
    if letter in vowels:
        found[letter] +=1
for k in sorted(found):#用k表示键；sorted函数可以按字母顺序输出
    print(k,'was found',found[k],'times(s)') #found[k]表示访问其关联值